1. Field
Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to response frame generation for transmissions using packets having increased symbol lengths or cyclic prefix lengths in relation to the preamble of the packet.
2. Background
Several challenges face wireless communications systems, such as WiFi systems. For example, there is a demand for WiFi systems to operate robustly in the outdoor environment.
In typical outdoor environment, the delay spread is much larger than those indoors so it requires the large cyclic prefix (CP or guard interval) in an OFDM symbol. Delay spread generally refers to the difference between the time of arrival of the earliest significant multipath component and the time of arrival of the latest multipath component. To keep the overhead of CP under control, generally a longer CP requires a longer OFDM symbol.
Unfortunately, a longer OFDM symbol can carry multiple times of more information bits than a normal duration OFDM, which may cause a challenge to the receiver to process the increased number of information bits in time to meet a required response timeline.